Using the lmodern package, I had the typical font size issues in math mode: for example the sums were not large enough in some of my equations. To solve this I followed egreg's answer to the following question: sum symbol in tikzposter too small
The solution works for the sums but now my brackets are not scaled correctly anymore. Making a minimal working example I noticed that the issue is related to the fourier package. So I suppose there are incompatibilities somewhere. I know fourier has incompatibilities with other math fonts packages such as mathptmx, in my case it might be related to lmodern. Is it possible to use fourier and lmodern and avoid the scaling issues I have with my equations?
MWE:
\documentclass[a4paper, 12pt, twoside,openright]{report}
\usepackage{lmodern}
\usepackage[upright]{fourier}
% declare `cmex` to be arbitrary scalable
\DeclareFontShape{OMX}{cmex}{m}{n}{
<-7.5> cmex7
<7.5-8.5> cmex8
<8.5-9.5> cmex9
<9.5-> cmex10
}{}
\SetSymbolFont{largesymbols}{normal}{OMX}{cmex}{m}{n}
\SetSymbolFont{largesymbols}{bold} {OMX}{cmex}{m}{n}
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage{bm}
\begin{document}
\begin{equation}
U_{qq} = \sum_{i < j \leq N_m} q_i q_j \left[ \sideset{}{'}\sum_{\bm{n}} \frac{\text{erfc}(\alpha \lvert\bm{r}_{ij} + L\bm{n}\rvert)}{\lvert\bm{r}_{ij} + L\bm{n}\rvert} + \frac{1}{\pi L} \sum_{\bm{n} \not= 0} \frac{1}{n^2} \exp(- \frac{\pi^2 n^2}{\alpha^2 L^2} + \frac{2 \pi i}{L} \bm{n} \cdot \bm{r}_{ij}) \right]
\end{equation}
\end{document}
fourier
. If it isn't, then remove\usepackage{lmodern}
and the part from\DeclareFontShape
to the second\SetSymbolFont
.lmodern
.